This invention relates to rotary mechanisms. More specifically, it relates to improved means for lubricating seals in such mechanisms.
Prior art of possible relevance includes the following U.S. Pat. No. 3,213,837 issued Oct. 26, 1965 to Keylwert; U.S. Pat. No. 3,261,334 issued July 19, 1966 to Paschke; and U.S. Pat. No. 23,343,526 issued Sept. 26, 1967 to Peras.
In rotary mechanisms such as trochoidal mechanisms or slant axis rotary mechanisms, the biggest impediment to extensive use of the same as pumps, engines, motors, expanders, or the like, has been difficulty in achieving reliable sealing of seals such as apex seals, end seals, peripheral seals, or the like. A variety of approaches have been taken as exemplified by the above identified prior art whereby a lubricant is directed to the vicinity of the seals to minimize wear.
For example, in the above identified Paschke patent, oil flowing through cooling passages in the rotor can be directed to cup-like elements received in seal receiving grooves and closing passages. Due to minute movement of the cup-like elements during operation, the oil will be smeared on the walls of the seal receiving groove to provide lubrication.
The principal difficulty of the Paschke approach is that no means are provided whereby the quantity of oil provided to each seal receiving groove can be accurately metered. Consequently, the Paschke design can result in relatively high oil consumption.
Peras illustrates one means by which quantities of oil may be metered relatively accurately for seal lubrication purposes by means of a conduit in a rotor extending to seals and periodically alignable with a pressurized oil passage in the shaft whereby pressurized oil, during alignment of the passage and the conduit, will be directed to the seals for lubrication purposes.
To preclude backflow in the oil conduit within the rotor as well as to prevent the entry thereinto of combustion gases or gases under pressure, Peras discloses the use of check valves in connection with the conduits and passages. While this approach works relatively well, it is expensive because of the need to provide the check valve elements.